I believe that's a felony.
Where? In Oregon, I believe it is now a felony to maliciously kill someone's pet, but a feral cat? C'mon. The law, again in Oregon, doesn't allow people to have a dog off-leash in game-bird nesting habitat during certain months.
"I believe that's a felony."
In California it has been allowed with clarity since 1991 to shoot roving dogs and cats in agricultural and forested areas.
The only way it would be a felony is to shoot the animal to wound it and then deliberately let it suffer. That is just cruelty. A nice headshot with a .45 vaporizes most cat heads on impact and is very humane.